Acute toxicity assessment of nine organic UV filters using a set of biotests

Marcin Stec,Aleksander Astel 한국독성학회 2023 Toxicological Research Vol.39 No.4

UV filters in environmental compartments are a source of concern related to their ecotoxicological effects. However, little is known about UV filters’ toxicity, particularly those released into the environment as mixtures. Acute toxicity of nine organic UV filters benzophenone-1, benzophenone-2, benzophenone-3, 4-methoxy benzylidene camphor, octocrylene, ethylhexyl methoxycinnamate, 2-ethylhexyl salicylate, homosalate, and butyl methoxydibenzoylmethane was determined. UV filter solutions were tested as single, binary, and ternary mixtures of various compositions. Single solutions were tested using a set of bio tests, including tests on saline crustaceans (Artemia franciscana), freshwater crustaceans (Daphnia magna), marine bacteria (Aliivibrio fischeri), and freshwater plants (Lemna minor). The tests represent different stages of the trophic chain, and hence their overall results could be used to risk assessment concerning various water reservoirs. The toxicity of binary and ternary mixtures was analyzed using the standardized Microtox ® method. Generally, organic UV filters were classified as acutely toxic. Octocrylene was the most toxic for Arthemia franciscana ( LC50 = 0.55 mg L– 1) and Daphnia magna ( EC50 = 2.66–3.67 mg L– 1). The most toxic against freshwater plants were homosalate ( IC50 = 1.46 mg L– 1) and octocrylene ( IC50 = 1.95 mg L– 1). Ethylhexyl methoxycinnamate ( EC50 = 1.38–2.16 mg L– 1) was the most toxic for marine bacteria. The least toxic for crustaceans and plants were benzophenone-1 ( EC50 = 6.15–46.78 mg L– 1) and benzophenone-2 ( EC50 = 14.15–54.30 mg L– 1), while 4-methoxy benzylidene camphor was the least toxic for marine bacteria ( EC50 = 12.97– 15.44 mg L– 1). Individual species differ in their sensitivity to the tested organic UV filters. An assessment of the toxicity of mixtures indicates high and acute toxicity to marine bacteria after exposition to a binary mixture of benzophenone-2 with octocrylene, 2-ethylhexyl salicylate, or homosalate. The toxicity of mixtures was lower than single solutions predicting antagonistic interaction between chemicals.

Effect of CO2 addition on lignite gasification in a CFB reactor: A pilot-scale study

Marcin Stec,Andrzej Czaplicki,Grzegorz Tomaszewicz,Krzysztof Słowik 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.1

The addition of carbon dioxide to the gasification media during lignite gasification is introduced. The paper presents thermodynamic grounds of CO2 enhanced gasification using a simplified equilibrium model. Experimental tests conducted using a pilot-scale circulating fluidized bed gasifier are discussed. Detailed analysis of the CO2/ C ratio on process conditions, namely on the process gas composition, lower heating value and H2/CO ratio, is provided. Process gas composition implies that the gas is suitable for heat and power generation. Alternatively, CO2 enhanced gasification could be considered as a carbon capture and utilization technology when external, renewable heat supply to the process is used. The results thus obtained are the initial step toward development of the CO2 enhanced gasification process.

Incorporating Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio in Place of Neutrophil Count and Platelet Count Improves Prognostic Accuracy of the International Metastatic Renal Cell Carcinoma Database Consortium Model

Pawel Chrom,Rafal Stec,Lubomir Bodnar,Cezary Szczylik 대한암학회 2018 Cancer Research and Treatment Vol.50 No.1

Purpose The study investigated whether a replacement of neutrophil count and platelet count by neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) within the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model would improve its prognostic accuracy. Materials and Methods This retrospective analysis included consecutive patients with metastatic renal cell carcinoma treated with first-line tyrosine kinase inhibitors. The IMDC and modified-IMDC models were compared using: concordance index (CI), bias-corrected concordance index (BCCI), calibration plots, the Grønnesby and Borgan test, Bayesian Information Criterion (BIC), generalized R2, Integrated Discrimination Improvement (IDI), and continuous Net Reclassification Index (cNRI) for individual risk factors and the three risk groups. Results Three hundred and twenty-one patients were eligible for analyses. The modified-IMDC model with NLR value of 3.6 and PLR value of 157 was selected for comparison with the IMDC model. Both models were well calibrated. All other measures favoured the modified-IMDC model over the IMDC model (CI, 0.706 vs. 0.677; BCCI, 0.699 vs. 0.671; BIC, 2,176.2 vs. 2,190.7; generalized R2, 0.238 vs. 0.202; IDI, 0.044; cNRI, 0.279 for individual risk factors; and CI, 0.669 vs. 0.641; BCCI, 0.669 vs. 0.641; BIC, 2,183.2 vs. 2,198.1; generalized R2, 0.163 vs. 0.123; IDI, 0.045; cNRI, 0.165 for the three risk groups). Conclusion Incorporation of NLR and PLR in place of neutrophil count and platelet count improved prognostic accuracy of the IMDC model. These findings require external validation before introducing into clinical practice.

Slide Session : OS-RHEU-06 ; Rheumatology : Impaired Functional Capacity in Patients with Systemic Sclerosis is Related to the Right Ventricle Dysfunction

( Eugene J Kucharz ),( Katarzyna Mizia Stec ),( Klaudia Gieszczyk Strozik ),( Agnieszka Sikora Puz ),( Maciej Haberka ),( Magdalena Mizia ),( Jadwiga Pajak ),( Jan Baron ),( Katarzyna Gruszczynska ),( 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Systemic sclerosis (SSc) is characterized by cardiovascular abnormalities which may affect patient`s clinical symptoms. The study was designed to assess whether the impaired exercise tolerance in patients with SSc without overt cardiopulmonary complications is related to the left ventricle (LV) or right ventricle (RV) dysfunction and vascular remodeling. Methods: Forty seven patients (F/M:36/11;age51.7±9.9) with defi nite SSc and clinical symptoms of heart failure (NYHA I/II) were enrolled into the study. In all the patients, pulmonary arterial hypertension (PAH), pulmonary fi brosis, left ventricle (LV) systolic dysfunction and valvular heart diseases were excluded. The following tests were performed: echocardiography, ultrasound vascular indexes: fl ow mediated dilatation, nitroglycerin mediated dilatation and arterial tonometry parameters: pulse wave velocity, pulse pressure and augmentation index. The above indexes were related to the 6 minute walk test (6MWT) Results: Results: The 6MWT mean value was 440.0±72m. LV diastolic dysfunction parameters did not correlate with 6MWT. RV systolic dysfunction (fraction area change<32%), decreased tricuspid annular plane systolic excursion (TAPSE < 20mm) or low peak systolic velocity of lateral tricuspid annulus (TDI: RV S` <20cm/s) were found in 1(2.1%), 5(10.6%), 43(91.5%) patients, respectively. The 6MWT values correlated with TAPSE (r=0.318, p=0.030) and TDI: RV S` (r= -0.295, p=0.048). There were no signifi cant correlations between ultrasound and arterial tonometry parameters and 6MWT values. Conclusions: After exclusion of typical causes of low exercise capacity in SSc patients, the shortened 6MWT distance observed in this group seems to be related to the RV systolic impairment, and this fi nding supports regular echocardiographic screening for early detection of cardiac complications in SSc.

Orthogonal lipid sensors identify transbilayer asymmetry of plasma membrane cholesterol

Liu, Shu-Lin,Sheng, Ren,Jung, Jae Hun,Wang, Li,Stec, Ewa,O'Connor, Matthew J,Song, Seohyoen,Bikkavilli, Rama Kamesh,Winn, Robert A,Lee, Daesung,Baek, Kwanghee,Ueda, Kazumitsu,Levitan, Irena,Kim, Kwang NATURE PUBLISHING GROUP 2017 NATURE CHEMICAL BIOLOGY Vol. No.

<P>Controlled distribution of lipids across various cell membranes is crucial for cell homeostasis and regulation. We developed an imaging method that allows simultaneous in situ quantification of cholesterol in two leaflets of the plasma membrane (PM) using tunable orthogonal cholesterol sensors. Our imaging revealed marked transbilayer asymmetry of PM cholesterol (TAPMC) in various mammalian cells, with the concentration in the inner leaflet (IPM) being -12-fold lower than that in the outer leaflet (OPM). The asymmetry was maintained by active transport of cholesterol from IPM to OPM and its chemical retention at OPM. Furthermore, the increase in the IPM cholesterol level was triggered in a stimulus-specific manner, allowing cholesterol to serve as a signaling lipid. We found excellent correlation between the IPM cholesterol level and cellular Wnt signaling activity, suggesting that TAPMC and stimulus-induced PM cholesterol redistribution are crucial for tight regulation of cellular processes under physiological conditions.</P>